I think fidelity is the ideal. However, we are but human. I remained faithful to my ex for 25 miserable, wretched, years. Not that I didn't have offers, I did, but I "did my duty" by him. Kept my vows. I don't think he did but it was my choice to do so. And sometimes wonder why I bothered, as it turned out that he had never believed our second child was his anyway! Much later, after being divorced for many years, I met with a man whose wife hadn't been intimate with him for ten years. He had always just put up with it, but we became very close and had an affair. I'm not proud of it, but neither am I ashamed. He would never have cheated on her if their marriage had been a full one, indeed I wouldn't have condoned it. In fact there came a day when she, having talked with her friends, decided that she was being unfair to him and wanted them to be a "normal" married couple again. He asked me if that would make a difference, and I had to say yes, it would. That was the end of the affair. I have often thought that she'd twigged to something happening, though he was convinced she had no idea, and that's why she made a change. Should he have put up with a joyless marriage indefinitely? Should he have told her and broken up the marriage? I don't know and I don't have the right to judge.